Boiler with superheater



B. BROIDO 5011mm 111's Surmashn mm mm. 1922 2 sum-sum 1 flen/am/h ru INVENTOR BY M 413 ATTORNEY Nov. 22, l 927.

B. BROIDQ BOILER WITH SUPERHEATER iled March 12f. 1922 Shuts-Sheet INVENTOR flan (2mm Bra/do V BY 3 %.L/&

ATTORNEY Patented Nov. 22, 1927.

UNITED STATES PATENT OFFICE.

. BENJAMIN BROIDO, OF NEW YORK, N. Y., ASSIGNOB TO THE SUPEBHEATEB COMPANY,

, OF NEWYORK, N. Y.

BOILER WITH SUPEBHEATEB.

Application filed larch 18, 1922. Serial No. 543,321.

My invention relates primarily to structures in which a superheater is intimately associated with the boiler, although it is also applicable where the two are housed separately. Modern practice demands high degrees of superheat and this can be obtained only by placing the superheater at a point where the gases coming into contact with it have not been cooled too much by intervening boiler surface. The steam flowing through the super-heater on its way from the boiler to the engine abstracts heat from the superheater fast enough to prevent any undue increase in the temperature of the super 16 heater walls and consequent injury to the superheater. When, however, there is no flow of steam through the superheater as during periods when the engine is shut down or when the boiler is being brought up to pressure, it may become necessary to protect the superheater against the danger of burning out; and my invention has for one of its ObJGCtS the rovision of improved protective means for t is purpose.

There are also other reasons why it may, under some circumstances, be desirable to have a flow of steam through the superheater at times when no steam is being withdrawn from the boiler for use, and my invention is equally intended for such cases.

By way of illustrating my invention I show it in the accompanying drawings aplied to two boilers of different types. This it will be understood is illustrative onlymlrd not by way of limitation. In these drawings Fig. 1 shows in side elevation a boiler with so-called' upright tubes with my invention applied to it, the near wall of the housing being omitted for purposes of clar- 49 ity; Fig. 2 shows a top new of the same boiler, the top wall being left off to simplify the drawing. Figs. 3 and 4 show the invention applied to another type of boiler in a somew at modified form, the two views correspondin to those of Figs. 1 and 2 respectively an the front and top walls being likewise omitted...

The boiler illustrated in Figs. 1 and 2 is of a well-known commercial type and ma 52 be briefly described as follows: Y

The ree upper drums 1, 2, and 3 are connected to the lower, drum 4 by bundles of tubes 5, 6, and 7 respectively. The structure is enclo ed in a housing 8 in the front part of which is located a furnace 9 and at the rear of which is the connection 10 to the stack. Suitable bafiling directs the products of combustion from the furnace 9 over the tubes 5, 6, and 7 to the connection 10. In boilers of this general description various locations for t e superheater have been chosen at different times, among them the one illustrated in the drawing. The superheater 11 is by way of illustration located ad acent to the front wall abovethe furnace 9 in which location a very high degree of superheat can be obtained. 12 is an arch to protect the lower end of the superheater against the intense radiant heat from the fuel bed. Ordinarily steam is carried from the middle boiler drum to the superheater by a suitable connection, has its temperature raised during its passage through the superheater, and then is carried to the point of use.

' 'The drums 2 and 3 of the boiler are connected with each other by means of a lower set of tubes 13 and an upper set 14. Simi* larly there is a lower set of tubes 15 connecting the middle and front drums 2 and 1 but the usual upper set connecting these two drums is omitted where my invention is used. The water level is indicated in the three drums by a horizontal dotted line.

27 is a safety valve leading from the steam space of drum 2.

The superheater itself comprises a saturated steam header- 16 and a su rheated steam header 17 and a set of tubuiii i' superheater elements or units 18 whose two ends are connected respectively to the two headers. A connection 19 establishes communication between the front drum 1 and one end of the saturated header 16 while a second connection 20 establishes communication from the middle drum 2 to the opposite end of the saturated header 16. The superheated steam header 17 is closed at its two ends and has a connection21 to which is attached the steam pipe 22 which carries the tteam to the desired point and has in it a valve or throttle 23.. The saturated steam header 16 is subdivided into two chambers 24 and 25 by means of the partition 26. This partition, it will be noted, is very much closerto one end of the header 16 than to the other, so that a comparatively small number of elements open into the chamber 25.

The operation of my invention will now be described. In boilers of this type, much the greatest part of the steam generated is generated in the tubes of the bank 5 and by them delivered to the drum 1. A small part of the steam is generated in the second and carried to the superheater. I have mentioned above that I omitted these connecting tubes. I take all of the steam which is delivered by tubes 5 into drum 1 directly off from this drum by the pipe 19 and carry itto the chamber 24 of the header 16. From this chamber, the throttle 23 being open, the steam flows through the superheater elements 11 and is by them, after having its temperature raised,delivered to header 17 whence it flows to the point of consumption by way of pipe 22. The steam delivered by ipes 6 to drum 2 reaches chamber 25 of eader 16 by means of pipe 20, leaves this chamber to flow through those superheater elements 11 which are connected to this chamber, being delivered by those elements to header 17 and likewise flowing to the point of use through pipe 22.

The partition 26 should be so placed with regard to the length of the header 16 that the chambers 24 and 25 are in substantially the same ratio as the amounts of steam delivered into drums 1 and 2 respectively. If desired, this partition can obviously be made adjustable in position audit is not deemed necessary to illustrate this.

The apparatus functions as just described aslong as the valve or throttle 23 is open and the operation is normal. When the throttle is closed the relative proportion of the steam delivered to drums 1 and 2 respectively remains about as before. The

ressure in drum 1 will, therefore, at once become higher than that in drum 2 and this is enhanced by the fact that the steam space in drum 2 is considerably larger than that in drum 1, drum 2 being at a higher level than drum 1 and the space above the water level therefor bein greater in it than in drum 1. As a resu t, a flow of steam from drum 1 will occur through pipe 19 to chamber 24 of header 16, thence through those superheater elements communicatin with chamber 24 of header 17, thence t rough those superheater elements communicating with chamber 25 of the latter chamber an thence through pipe 20 to drum 2. This flow will carry away heat from superheater elements 1 1 at a suflicient rate to protect them against injury. When the pressure raises sufilciently to open the safety valve 27, the flow in the manner just described continues and continues to protect the elements. It will be seen that the elements are also which are nearest to the fire and this steam circulates through the elements-to drum 2. Referrin now to Figs. 3 and 4, the boiler used for il ustration in this case comprises two horizontal drums 28 and 29 from which extend downward the two headers 30 and 31 which are connected by Water tubes 32. The Whole structure is enclosed in a housing 8 in the front part of which is the furnace 9. The gases leaving the furnace 9 are directed in their passage over the tubes 32 by suitable bathing.

The superheater is here, by way of illustration, shown behind the bridge wall 33 al though it may evidently have some other position. It again comprises two headers 16 and 17 to which are connected the superheater elements 11. i p

To apply my invention to a boiler of this type I subdivide the space in the drums 28 and 29 into two portions by means of a partition 34. This partition does not extend entirely to the bottom of the drums but terminates short of it, extending, however, well below the water level 35. The partition of each drum is very much nearer the front end than the rear, dividing off a smaller steam space 36 at the front end from the larger steam space 37 at the rear. Connections 38 and 39 lead from the two spaces 36 to a common pipe 40 which is connected to one end of the header 16. From the opposite end of the header 17 there extends a pipe 41 which conveys the steam to pipe 42 and so to the point of use. Pipe 42 is provided with a valve or throttle 43. From steam spaces 37 and each of the drums 28 and 29 their connections 44 and 45 extend to the common pipe 46 which communicates with pipe 41 y means of the Y 47. 48 and 49 are two safety valves.

In a boiler of this type practically all of the steam generated Wlll flow upward in the tubes 32 and reachthe front header 30 of the chamber 36. Only a negligible amount of steam will be liberated into space 37.

Durin the normal operation of a boiler equipped as described, that is, while valve or throttle 43 is open, steam delivered in the chamber 36 will reach the header 16 of the superheater b means of ipe 40, will flow through the e ements 11, emg superheated 1n dOlIlg so, reach header 17 and flow thence through pipe 41 to pipe 42, to the point of use. Any steam that should be delivered to s ace 37 of the drums 28 and 29 will join t e current of superheated steam at the Y 47. The amount of this latter steam is so small that its influence on the degree of superheat may well be ne lected.

,When, now, the thrott e or valve 43 is closed the steam generated will still be delivered into chambers 36 and 37 in substantially the same proportions as before. The pressure in chamber 36 will, therefore, at once rise above that in 37 and a flow of steam from the former to the latter will occur by -way of pipe 40, header 16, elements 11,

header 17, pipe 41, pipe-46, and pipes 44 and 45. This flow will serve to cool the superheater elements below the point of danger. When the boiler pressure rises sufliciently to open the safety valves 48 and 49 the flow in the direction just outlined will continue and the superheater elements will continue to be protected. In this case, also the protection occurs as just described during periods of firing up. Steam generated in the lower tubes 32 will reach space 36 and flow thence through the superheater to space 37 protecting the superheater.

It will be noted that the underlying idea in the two forms described is the same although in one of them the partition is used ,in the saturated steam header and none in I the other. Whether or not the steam from the larger space, that is the space into which the smaller amount of steam is delivered directly from the boiler, should be carried through some of the superheater elements as in the form of Figs. 1 and 2 or should be allowed to join the superheated steam directly without itself, being superheated is evidently a matter of choice and will be determined largely by the question of what relative amount of steam is delivered into the larger chamber.

It will be obvious that in practicing my invention some departure from the specific -forms herein descrlbed may occur without losing the spirit of the invention.

\Vhat I claim is z p 1. In apparatus of the class described, the combination of a boiler having two separated steam spaces one of which is several times as large as the other into the first. and smaller of which more of the steam is delivered upon its generation than into the second; a superheater; a pipe connecting said first space to the superheater inlet; a second pipe leading from the superheater outlet directly to the point of use; and a conduit putting said second space into communication with the outlet of the superheater.

2. In apparatus of the class described, the combination of a boiler having two separated s'team spaces into the first of'which more of the steam is delivered on its generation than into'the second; a superheater comprising two headers and a plurality of tubular elements whose ends are secured one to each header; a pipe connecting the first space to one end of one of the headers; a pipe connecting the second space to the other end of the same header; a partition in the header dividing its interior so that a relatively small number of the elements open into the part adjacent to said second connecting pipe; and. a delivery pipe leading from the other of said headers.

BENJAMIN BROIDO. 

